A numerical solution is presented for the dynamic analysis of gas lubricated noncontacting mechanical face seals having a single grounded flexibly mounted stator. Seal dynamics is solved in axial and angular modes of motion. Both the Reynolds equation and the equations of motion are arranged into a single state space form, allowing the fluid film lubrication and the dynamics to be solved simultaneously. The resulting set of equations is solved using a high-order multistep ordinary differential equation solver, yielding a complete simulation for the seal dynamic behavior. Examples of seal motion are given in detailed transient responses. The stability threshold is investigated to gauge the influence of seal parameters such as inertia, speed, coning, and the direction of sealed pressure drops. The results show two modes of instability: (1) When the inertia effect is larger than a critical value, the natural response of the seal grows monotonically in a half-frequency-whirl mode. (2) When the seal coning is less than some critical value in an outside pressurized seal, the minimum film thickness diminishes because of hydrostatic instability, and face contact occurs. Conversely, an inside pressurized seal is shown to be hydrostatically stable and have a superior dynamic response at any coning.

1.
Etsion
,
I.
,
1982
, “
A Review of Mechanical Face Seal Dynamic
,”
Shock Vibr. Dig.
,
14
, No.
3
, pp.
9
14
.
2.
Etsion
,
I.
,
1985
, “
Mechanical Face Seal Dynamics Update
,”
Shock Vibr. Dig.
,
17
, No.
4
, pp.
11
16
.
3.
Etsion
,
I.
,
1991
, “
Mechanical Face Seal Dynamics 1985–1989
,”
Shock Vibr. Dig.
,
23
, No.
4
, pp.
3
7
.
4.
Green
,
I.
, and
Etsion
,
I.
,
1983
, “
Fluid Film Dynamic Coefficients in Mechanical Face Seals
,”
ASME J. Lubr. Technol.
,
105
, No.
2
, pp.
297
302
.
5.
Green
,
I.
, and
Etsion
,
I.
,
1985
, “
Stability Threshold and Steady-State Response of Noncontacing Coned-Face Seals
,”
ASLE Trans.
,
28
, No.
4
, pp.
449
460
.
6.
Cha
,
E.
, and
Bogy
,
D. B.
,
1995
, “
A Numerical Scheme for Static and Dynamic Simulation of Subambient Pressure Shaped Rail Sliders
,”
ASME J. Tribol.
,
117
, pp.
36
46
.
7.
Leefe, S., 1994, “Modeling of Plain Face Gas Seal Dynamics,” 14th International Conference on Fluid Sealing, BHR Group Conference Series, No. 9, pp. 397–424.
8.
Shapiro
,
W.
, and
Colsher
,
R.
,
1974
, “
Steady State and Dynamic Analysis of a Jet-Engine, Gas Lubricated Shaft Seal
,”
ASLE Trans.
,
17
, No.
3
, pp.
190
200
.
9.
Castelli
,
V.
, and
Pirvics
,
J.
,
1968
, “
Review of Numerical Methods in Gas Bearing Film Analysis
,”
ASME J. Lubr. Technol.
,
90
, pp.
777
792
.
10.
Green
,
I.
, and
Etsion
,
I.
,
1986
, “
Nonlinear Dynamic Analysis of Noncontacting Coned-Face Mechanical seals
,”
ASLE Trans.
,
29
, No.
3
,
383
393
.
11.
Miller, B., and Green, I., 1999, “Numerical Formulation for the Dynamic Analysis of Spiral-Grooved Gas Face Seals,” presented at the STLE/ASME Tribology Conference, Seattle, WA, October 1–4, 2000.
12.
Shampine, L. F., 1994, Numerical Solution of Ordinary Differential Equations, Chapman and Hall, New York.
13.
Green
,
I.
, and
Etsion
,
I.
,
1986
, “
Pressure and Squeeze Effects on the Dynamic Characteristics of Elastomer O-Rings Under Small Reciprocating Motion
,”
ASME J. Tribol.
,
108
, No.
3
, pp.
439
445
.
14.
Lee
,
A. S.
, and
Green
,
I.
,
1995
, “
Physical Modeling and Data Analysis of the Dynamic Response of a Flexibly Mounted Rotor Mechanical Seal
,”
ASME J. Tribol.
,
117
, pp.
130
135
.
15.
Gross, W. A., 1980, Fluid Film Lubrication, John Wiley & Sons, New York.
16.
Green
,
I.
,
1987
, “
The Rotor Dynamic Coefficients of Coned-Face Mechanical Seals with Inward or Outward Flow
,”
ASME J. Tribol.
,
109
, No.
1
, pp.
129
135
.
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